JPH036335B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a fuel injection pump for an internal combustion engine, comprising one plunger driven by a cam drive, the cam drive having one rotating member and a stationary and a member which is arranged in the same direction and is rotatable in relation to the operating parameters and the operating temperature, both parts being connected to each other via a cam surface and via a speed governor. The governor has one control lever which can be operated externally to the injection pump between one adjustable idle stop and one full load stop. It has a control spring inside the injection pump which can be adjusted via a temperature-related regulating element which acts on a lever connected to the regulating shaft. and the adjusting shaft is connected to an adjusting element for temperature-related rotational adjustment of the stationary rotatable element of the cam drive, said adjusting element simultaneously controlling the fuel injection quantity. It relates to a type that also acts on one member that affects the

In the case of known fuel injection pumps, mechanisms that operate independently of each other are used to increase the amount of fuel at startup, to adjust the idling speed, and to adjust the injection timing in relation to the speed. However, the demands placed on diesel engines have made it necessary to introduce engine temperature-related control operations into the functioning of the injection pump. For example, it is already known to change the zero or rest position of the control lever of a fuel injection pump via an expansion member and a Bowden cable, so that the idling speed increases as the engine temperature increases. known to reduce numbers. Furthermore, 1
It is known to adjust one hydraulic injection timing regulator, ie the piston of a timer, via two thermostats "early" during a cold start. It is also known to reduce the starting charge via a single thermostat as the starting temperature increases. Individually, each of these known measures can be said to be a control operation without any problem. but,
Application of just one of these treatments is often not sufficient. On the other hand, employing these multiple control operations makes the injection pump undesirably bulky and expensive due to the increased number of components required. Moreover, the problem arises of synchronizing the various control values for the various detectors and transducers with one another.

The objects of the present invention are to control the injection timing "earlier" at the time of cold start, to reduce the amount of additional starting fuel in accordance with the rise in engine temperature after starting, and to control the idling speed in accordance with the rise in engine temperature. The object of the present invention is to enable three control operations including the lowering control to be carried out simultaneously, and to prevent the volume of the fuel injection pump from becoming undesirably large. This object has been achieved by the features shown in the claims.

With the fuel injection pump according to the invention as defined in the patent claims, it is possible in a simple manner to incorporate a number of temperature-related control operations into the injection pump regulation function by simply and reliably synchronizing the individual control values. This gives you the advantage of being able to. Another significant advantage is that one basic device with many control operation possibilities can be produced in mass production, and in practice one or many control operation possibilities are possible depending on the needs of the internal combustion engine. You can use . Therefore, in many cases even specially equipped internal combustion engines, such as turbochargers, for example, can be provided with the same type of injection pump as in standard internal combustion engines.

The invention will now be explained in detail with reference to the embodiment shown in the drawings: In the case of the fuel injection pump shown in FIG.
A barrel 2 is arranged inside the casing 1 and has a barrel bore 3 .
Within this barrel inner hole 3, one plunger 4 performs reciprocating motion and rotational motion. The working chamber 5 formed in the barrel bore 3 is supplied with fuel during the suction stroke of the plunger 4 from a suction chamber 7 arranged in the casing 1 via one suction hole, and the plunger 4 receives this fuel. During the discharge stroke, fuel is pumped through discharge conduits 8 (only one shown) to the individual injection nozzles. 1 in the plunger 4 which branches off from the working chamber 5 for fuel supply and distribution to the discharge conduit 8.
Two central holes 9 are used, to which are connected one distribution groove 10 on the circumference of the plunger 4, which distribution groove 10 is connected to the circumference of the plunger 4.
With the rotational movement of , the discharge conduits 8 are sequentially aligned with each other.

The plunger 4 is driven via a cam drive device 11. The cam drive 11 is connected to the plunger 4 and to a roller ring 13 carrying rollers 12 as substantially stationary members of the cam drive 11, as clearly shown in FIG. One front cam plate 14 is provided as a rotating member that rotates on a roller 12. Cam disk 14 as well as plunger 4 are rotated entrained by drive shaft 15 via a coupling (not shown). A roller ring 13, which is fixedly mounted in the housing 1, is controlled at a certain angle by means of the piston of a hydraulic timer 16 for adjusting the injection start, depending on the operating parameters such as the rotational speed and the temperature of the internal combustion engine. can only be rotated. The stroke drive of the plunger 4 is effected by a cam disk 14 against the force of a return spring 17.

The suction chamber arranged in the housing 1 as well as the timer 16 are supplied with fuel by a fuel pump 18 . The pressure of the fuel pump 18 is controlled according to the engine speed, and the timer 1 is set depending on the fuel pressure.
6 causes a corresponding adjustment movement in the piston.

In order to control the fuel injection quantity, a control sleeve 20, which is arranged in the part of the plunger 4 extending into the suction chamber 7, is used as a fuel injection quantity adjustment element. This control sleeve 20 controls the opening of one lateral hole 21 intersecting the central hole 9 in the plunger 4 . The higher the control sleeve 20 is on the plunger 4 as shown in FIG.
1 is controlled to open late with the plunger stroke, that is, the injection amount increases. The opposite is true if it is located low. This control sleeve 20 is moved by a single mechanical speed governor 23. The speed governor 23 is equipped with one starting lever 24 supported at a point M1 and used as a starting fuel adjusting member. The speed sleeve 25 acts directly. The centrifugal speed governor mechanism is driven by the drive shaft 15 via one gear device 27. The starting lever 24 rests on a tensioning lever 29 via a relatively weak starting spring 28 . This tensioning lever 29 is also mounted at point M1 and is driven by the starting lever 24 with a corresponding stroke of the regulating sleeve 25. As this starting lever 24 comes into contact with the tension lever 29, first the idling spring 30 and then the control spring 3
1 is loaded. Operationally, these starting spring 28, idling spring 30, control spring 31
are placed one after the other. Since the idling spring 30 is weaker than the control spring 31, the control spring 3
The position of the lower suspension point 32 determines the initial tension of the idling spring 30 in the rest position, which corresponds to the idling of the tensioning lever 29 determined by one stop 33. The initial tension of the control spring 31 is determined by one control lever 34 . This control lever 34 is operated by the driver to adjust the lower suspension point 32, and changes the ratio of the injection amount to the rotational speed depending on the adjustment position.

An adjusting element in the form of a crinkle lever 35 also acts on the starting lever 24 . This shingle lever 35
The starting lever 24 is positioned via the triggering lever 24 and the tensioning lever 29 is swiveled into a position, ie a position in which the control sleeve 20 is pressed down and injection is no longer possible as seen in the figure. This crimping lever 35 also serves as a stop for the starting lever 24 in order to adjust the maximum starting increase. Shading lever 35
With the slight pivoting of the engine, the position of the control sleeve 20 and thus the start-up amount change accordingly. If a starting increase is undesirable, for example when the internal combustion engine is not cold, the starting lever 24 can be moved directly to the tensioning lever 29 by means of the shearing lever 35.
This prevents the amount from increasing at startup.

In order to be able to control the increase in idling or starting power in relation to the engine temperature, the starting position of the shingle lever 35 or the starting lever 24 or the starting position of the suspension point 32 or the control lever 34 can be adjusted using a temperature-sensitive adjustment member. It is sufficient to vary it by one idle stop which can be adjusted by. In the case of the shingle lever 35, the possible lever travel becomes smaller as the temperature increases, and in the case of the control lever 34, the possible travel between one full-load stop 41 and the idle stop increases as the temperature increases. Become.
In the case of this control lever 34, the load on the idling spring 30 at the position of contact with the idling stopper is further reduced as the temperature increases. As a result of such load reduction, the injection amount suppression control rotation speed during idling becomes a lower rotation speed.

In FIG. 2, the cam drive device 11 of the fuel injection pump is shown along the - line in FIG. Roller ring 13 with rollers 12 has one pin 3
Rotation is caused by a piston of a hydraulic timer 16 via 7. An eccentric pin 39 of an adjusting device 40 also engages as an adjusting element in one groove 38 of the roller ring 13, which forces the roller ring 13 into an early injection, especially during a cold start. It can be adjusted accordingly. It is also possible to effect such an early injection adjustment directly on the piston of the timer 16. In this case, the piston of the timer 16 is pushed and shifted in time for early injection when the engine is cold. Such an early injection adjustment can advantageously be carried out via a thermostat or a temperature-sensitive regulating element. Of course, this early injection adjustment can also be made by controlling the oil pressure that operates the piston of the injection timer 16. What is important is that the rotation of the roller ring in the "early" direction is carried out via one temperature sensor, which is activated by the same adjustment in the governor to increase the starting power or to change the idling speed. This means that it gives rise to proportions.

FIG. 3 shows a temperature sensor 42 or a temperature-sensitive regulating element which is arranged in the engine which is supplied with fuel by a fuel injection pump. This temperature sensor, which is constructed as a so-called expansion sensor, extends into a chamber 43 through which engine cooling water flows. As the temperature increases, the temperature sensor 42 pushes the piston 45 forward through the pin 44 against the force of the spring 46. Two Bowden cables 47 are fixed to the piston 45 and provide synchronous or simultaneous control of the movement of the shingle lever 35 and the control lever 34 and of the early injection adjustment of the timer 16. be able to. Of course, these control operations include three control operations: a control operation to "advance" the injection timing at startup, a control operation to decrease the amount increased at startup after startup, and a control operation to decrease the idling rotation speed. It is also possible to carry out only two of these via this temperature sensor.
According to the invention, however, it is also possible to control the fuel injection pump with a temperature sensor via only one Bowden cable.

An example of just one Bowden cable is shown in FIGS. 4 and 5. bowden cable 4
Angle piece 49 with one end on the injection pump side of 8
The other end is connected to a temperature sensor 42 on the internal combustion engine side. The cable 50 of the Bowden cable 48 is threaded into one guide pin 51 and fixed at its free end by a first set screw 52.
A second set screw 53 as a stopper is arranged in the middle of the free section of this cable 50,
This set screw 53 defines the starting position of the shear cutting lever 35.

The first set screw 52 acts on a guide pin 51 which can be displaced axially against the force of a spring 55 in an angled piece 54 fixed to the housing. A stopper adjustment member 56 used as an idling stopper is fixed to this guide pin 51.
The turning stroke of the control lever 34 can be increased or decreased. Thereby, it is possible to synchronously influence fuel injection amount control, idling control, and starting amount increase control. 1 via a synchronously operated second Bowden cable as shown in FIG.
Two control operations can be applied to injection timing adjustment.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of the fuel injection pump of the present invention;
Figure 2 is a cross-sectional view taken along the - line in Figure 1;
The figure is a longitudinal cross-sectional view of the engine temperature detector, Figure 4 is a plan view showing the adjustment member for increasing the starting amount and the adjustment member for idling speed, and Figure 5 is the example of Figure 4.
It is a diagram shown shifted by degrees. 1... Casing, 2... Barrel, 3... Barrel inner hole, 4... Plunger, 5... Working chamber, 6...
...Suction hole, 7...Suction chamber, 8...Discharge conduit, 9...
... Central hole, 10 ... Distribution groove, 11 ... Cam drive device, 13 ... Roller ring, 14 ... Cam disc, 15 ... Drive shaft, 16 ... Timer, 17 ...
...Return spring, 20...Control sleeve, 2
3... Speed governor, 24... Start lever, 25... Speed governor sleeve, 26... Centrifugal weight, 28... Start spring, 29... Tension lever, 30... Idling spring, 31... Control spring, 34... Control lever, 35... Shrink lever, 39... Eccentric pin, 40... Adjustment device, 42... Temperature detector, 43... Chamber, 44... Pin, 45... Piston, 46... ...Spring, 47...Bowden cable,
48... Bowden cable, 49... Angle piece, 51... Guide pin, 52... First set screw, 53... Second set screw, 54... Angle piece, 56... Stopper adjustment member.

Claims (1)

[Claims] 1 A fuel injection pump for an internal combustion engine, comprising one plunger 4 driven by a cam drive device 11, the cam drive device 11 having one rotating member 14 and a fixedly arranged fuel injection pump that controls operating parameters. and one member 13 which is rotatable in relation to the operating temperature, both members 14, 13.
are connected to each other via one cam surface,
It has one fuel injection amount adjustment member 20 that can be operated via a speed governor 23, which is arranged between one adjustable idling stop 56 and one full load stop outside the injection pump. It has a control spring 31 inside the injection pump which is adjustable via a control lever 34 which can be actuated at is an adjusting element 39 for temperature-related rotational adjustment of the stationary rotatable element 13 of the cam drive 11;
said adjusting member 42, 44, which operates in relation to temperature, in the type in which said adjusting member simultaneously acts on a member having an effect on the fuel injection quantity control; 45,
46 is connected to two Bowden cables, one Bowden cable is connected to the lever on the cam drive side and the other Bowden cable is connected to the idle stopper 56 of the control lever 34, so that the idle The stop 56 is held in one stop via a spring 55, and the other Bowden cable 48 is held in the idle stop 56 via a first locking screw 52 which can be fixed in position on the cable 50.
The idle stopper 56 can be adjusted in position by a set screw 52 against the force of the spring 55, and the Bowden cable 48 can be adjusted via a second set screw 53 on the cable 50. A fuel injection pump characterized in that starting levers 24 and 35 for adjusting the amount of injection at the time of starting the engine can be operated to adjust the increase in amount at the time of starting.